Question: Simplify the following expression: $k = \dfrac{r}{5t - 2s} - \dfrac{2s + 1}{5t - 2s}$ You can assume $r,s,t \neq 0$.
Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{r - (2s + 1)}{5t - 2s}$ $k = \dfrac{r - 2s - 1}{5t - 2s}$